Bullet seating depth Q

Theres nothing 'wrong' with testing at 300, on a calm day and with consistent form
The good advantage is being able to identify changes in a larger pattern better than a with smaller one @100
This may just be a good practice exercise toward being ready for when you use a new primer and when the
brass is either older or annealed or maybe new or ......
 
bigHUN said:
For now just to start my shooting season.... I am focusing for distance up to 300 M ....
What is an acceptable ballpark with SD that shall keep the groups tighter?
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SD of 10 is a good benchmark, especially on larger sample size firings of 30+ rounds

Make sure you retest your best and worst seating depths - results may surprise you

I'd suggest upping your samples from 5 rounds to at least 10 if you want to see the real truth
 
I usually do a ladder test first, this will (most of the time) identify the high node for further testing.

155 bullets are jump tolerant and using varget will easily net you 2900+ fps in the 45.5 - 47 grain range if you can seat them out (monitor for pressure).
 
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Adding to All this 100 yard groups are great to see IF your rifle likes the bullet powder seating depth etc etc combination
But does nothing to prove out if the load will shoot at distance .🤷🏼‍♂️
Need to get to 300 and 500 - 600 and see the results of 10-15 shots . because that’s where matches are shot a lot at .
Essentially important at Windy ranges as some bullets due to design or weight don’t STEER well , JMO RJ
 
iron cat said:
I don't worry about ES or SD as much as group consistency on the target .
If I find a powder /OAL length that works well, I shoot three different 5 shot groups to see if I can replicate it at 300 meters.
I rarely shoot at 100 meters.
Cat
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I agree completely, except I have no issues with shooting at 100. If it doesn't group at 100, it won't group at 300 and you can control a few environmental variables by shooting shorter ranges, it helps sorting out the gun/shooter/load from conditions. Just my 2 cents (remember what you paid for the opinion :)
 
paperslayer said:
I agree completely, except I have no issues with shooting at 100. If it doesn't group at 100, it won't group at 300 and you can control a few environmental variables by shooting shorter ranges, it helps sorting out the gun/shooter/load from conditions. Just my 2 cents (remember what you paid for the opinion :)
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The reason I rarely shoot at 100 meters is because the competitions I participate in start at 300.
I sometimes do load development for my hunting rifles at 100 however and zero them at 200.
Cat
 
Yesterday was a first day since mid March that the Temp reached 10+C, but the ground is still radiating cold.
I had a soar throat and a bit of coughing, didn't wanted to stretch the health.
The weatherman is not promising anything in a next week time, I must wait with these my tests.

I prefer shooting the tune tests at longer distance, the longest available is 300 @ SGC, or I shall go to Borden base.
Shooting 5 or 10 strings will make just one big ragged hole, nothing to read from there. 300 can show the spread.
 
bigHUN said:
Finally today a first visit to my range this year.
I did my very first powder re-load back in December, but unfortunately the weather didn't cooperate.
In meantime also I collected my full set of Wilson tools I may need for any sort of scenarios I have learned along the way of re-loading diy.


Lapua W308 brass (inherited, history unknown), powder Varget, bullet 155gn Sierra Match 2155, seating depth 0.033".
I had five batches of powder in increments from 46gn to 46.8gn to test 5 shot groups each. Testing @ 300 Meters, 17C, 33% hum, 1006.8mb.

#1 group of 5 - 46.0gn - Av 2994 fps
#2 group of 5 - 46.2gn - Av 2997 fps this group seem to me the tightest, 1.1" width and 1.5" height elongated in 45 deg to Right side.
#3 group of 5 - 46.4gn - Av 3017 fps
#4 group of 5 - 46.6gn - Av 3013 fps
#5 group of 5 - 46.8gn - Av 3051 fps

Me personally I don't like to see these high speeds, I may create in the future couple batches less powder sub 40gn and re-test for groups.
The next step I will do bullet seating in increments, probably start from current 0.033 and going up and down several steps in 0.003"

My Question is:

All what I have seen pictures online and forums - people testing seating depth @ 100M/y and usually three shots?
Why 100? Why not 200 or 300?
Any valid reason? I am just trying to learn how to read ...
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Lots of great opinions here, may I share mine? - and remember what you paid for it,

NOTHING wrong with starting at 100. If it doesn't group at 100, it sure as hell won't group at 300. Groups don't get smaller. 100 minimizes atmospheric interference, giving you better raw data.

Seating depth - in my opinion - is the holy grail of getting groups tight. The challenge is to seat your bullets in relation to the lands, and that can be a tricks measurement to make. One of the most effective little gizmos you can make is taking a fire-formed case and cutting 6 slits with a dremel into the neck to create "fingers" in the neck . Close the bolt on you slit case with a bullet in front and the lands will seat the bullet into the case. Keep this particular bullet, because you do a no-no and measure from the tip for setting up your die.

When you know the OAL length of a cartridge touching the lands, you can then load develop with jump, eventually switching to jam. Pressures will INCREASE as you jam, so start with an empirically know powder charge and work from there. Hornady and formerly Stoney Point also have good tools for measuring seating depth, but they are finicky.
 
About 3 shot groups...
... a good 3 shot group does not "prove' a load but it has meaning... if you can't shoot 3 shots in a small group you sure won't shoot more any smaller.

With a .308 Win I never started any closer to the lands than 15 thou and worked out for best depth.
 
You may be surprised with the method you used to find the lands. Depending on how much neck tension your brass had on the bullet, you could be in the lands still.

The lands start on a slope, so it is very easy to have no idea where youre at in relation to the lands if youre not using the "stick" method.


Dont necessarily have to remove the barrel IMO. Take the bolt out of your rifle, clean the chamber and throat. Put a cartridge in the chamber and push it home with your finger. Stand the rifle up on the butt, if the cartidge doesnt fall out by itself, you're in the lands. (Assuming the bullet runout isnt holding it in the free bore, and the shell itself isnt stuck.) There is a .001" window between being stuck in the lands, and not touching the lands.

Because the rifling starts very gradually(on a slope) with my hornady OAL gauge, if I lightly push the bullet into the rifling until it stops, I am easily .040" into the lands with a 15° slope starting the rifling.

Ultimately if you start wherever and move the seating depth to wherever and its shooting good, that's what counts. Knowing and starting at true 0 on the lands is going to be the least wasteful on components.

As a side note... I would recommend starting at true 0, minus .010".(or whatever is claimed as a good starting point for the bullet) And not touching the seat depth again until you have found the powder node. Once you have found the powder node, go ahead and make +/- .003 adjustments to tune it.

The problem with a recommended "go .030" off the lands" is.... most people likely truly dont have any idea where the land actually is. It is an arbitrary number that they're removing .030" from unless they know EXACTLY where the lands are. I think Speedys method tells a person EXACTLY where 0 is.

Someones .030" "off the lands" could very well still be .010" jam depending on how the starting point was derived. Some claim to run a .070 jump... is it actually .070... or did they jam it .040 into the lands to start and realistically it didnt start shooting good until they pulled it back .070 from their start...which would truly be a .030 jump.
 
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I failed to report back my reload testing results in May, this what I came up with (and documented) for tightest groups @ 300M and 200M:

Temp 13C, Hum 30%, Press 1024 mB
45.8 grain Varget researching in 0.2 grain increments, started incrementally with 5 shot groups and when got closer proceed with 10 shot groups.
and
Temp 15C, Hum 33%, Press 1017 mB
Seating depth of 0.026" from land, researching in 0.003" increments, started incrementally with 5 shot groups and when got closer proceed with 10 shot groups.
Average speed of 2989 fps out of last 26 shots (final seating depth 0.026").

I put the gun aside for now, and started building my own induction annealing machine.
I have about 200 brass to fully process for next step 500M, that will take me some decent elbowgreasing.

I am back to my airguns, shooting 50M and 100M BR rings for training and practice.
 
Better get a move on with your load development, the Ontario Rifle Association Provincial Championship matches are in Aug from the 15-17 and you can stay and shoot the DCRA CFRC matches from the 18-23. All at Mons range at CFB Borden.
 
bigHUN said:
Finally today a first visit to my range this year.
I did my very first powder re-load back in December, but unfortunately the weather didn't cooperate.
In meantime also I collected my full set of Wilson tools I may need for any sort of scenarios I have learned along the way of re-loading diy.


Lapua W308 brass (inherited, history unknown), powder Varget, bullet 155gn Sierra Match 2155, seating depth 0.033".
I had five batches of powder in increments from 46gn to 46.8gn to test 5 shot groups each. Testing @ 300 Meters, 17C, 33% hum, 1006.8mb.

#1 group of 5 - 46.0gn - Av 2994 fps
#2 group of 5 - 46.2gn - Av 2997 fps this group seem to me the tightest, 1.1" width and 1.5" height elongated in 45 deg to Right side.
#3 group of 5 - 46.4gn - Av 3017 fps
#4 group of 5 - 46.6gn - Av 3013 fps
#5 group of 5 - 46.8gn - Av 3051 fps

Me personally I don't like to see these high speeds, I may create in the future couple batches less powder sub 40gn and re-test for groups.
The next step I will do bullet seating in increments, probably start from current 0.033 and going up and down several steps in 0.003"

My Question is:

All what I have seen pictures online and forums - people testing seating depth @ 100M/y and usually three shots?
Why 100? Why not 200 or 300?
Any valid reason? I am just trying to learn how to read ...
Click to expand...
what make is the rifle
 
maynard said:
Better get a move on with your load development, the Ontario Rifle Association Provincial Championship matches are in Aug from the 15-17 and you can stay and shoot the DCRA CFRC matches from the 18-23. All at Mons range at CFB Borden.
Click to expand...
That is the plan.
I can process a batch of 150 probably in short time, but not sure how can I go to Borden to test @ 500 and 800 let say.
I've been there couple times as a spectator only, the Canadian competition the last time I visited.

struff55 said:
what make is the rifle
Click to expand...
I have no idea :) I got it from an older f-class shooter but through a friend.
It is a older Rem 700 based W308 SA single load, with a target synthetic stock couple people were modifying it in the past, the most mods I made DIY.
My another mod is a new bolt spring and an arca rail on bottom.
 
Big Hun, join the ORA. then get onto Target Score set up a profile and enter the match. There are also mid-week long range practices at Borden to allow you to get 1000 yard zeros. If you have a 300 yard zero you will need about 25 minutes of elevation from that to get to 1000.
 
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